Manufacture of lasts



P. F. w. c. KRIPPENDORF. MANUFACTURE OF LASTS. APPLICATION F|LED JULY H, 19I6.

Patented Mar. 30, 1920.

2 SHEETS SHEET 1- P. F. W. C. KRIPPENDORF.

MANUFACTURE OF LASTS.

APPLICATION FILED JULY 17, 1916. v v 1,335,062. Patented Mar. 30,1920.

2 SHEETS-SHEET 2- llNllllilhll STATES PATENT OFFICE,

PAUL F C. KIRIPPENLDORF, OF LYNN, MASSACHUSETTS, ASSIGNOIL T KRIPPENDORF KALCULAIOB, COMPANY, OF PQRTLAND, MAINE, GURPORAZKFION 0F JMEAINE.

MANUFACTURE 0].? LASTEE.

Specification of Letters Patent.

Patented Mar. St 19250.

Application filed July 17, 1916. Serial No. 109,749.

in the several figures.

This invention relates to the manufacture oi? lasts and comprises improved processes and machinery for such manufacture.

The last lathe at present used in last t'r'actories comprises a swing frame holding a model and a block which rotate on centers engaging their ends. A model wheel and cutter are co-axially mounted on two sliding carriages, the former guiding the frame through contact with the model, while the cutter trims oil? the block to corresponding shape. When the cutting is finished the last h: s a nub on each end, corresponding to the centers used to hold the model, and the ends of the last must therefore be finished by an independ out operation, out of the lathe. 'lhe linishing ot the ends, especially the toe tip, is an operation requiring the most extreme accuracy, as a slight departure from the correst shape at the toe tip is very noticeable.

Attempts havebeen made to perform this operation by machinery, but the machines heretofore devised have proven unsatisiao tory and have never gone into commercial use, They require the model and the last to be chucked in a a-accond copying lathe by their middle portions, and the (lilticulty of i0 chucking the model and last in exactly similar relation to the model wheel and cutter ters on the drawings indicating like parts terial at the ends of the last. Ekilled as these operators may be, such cut and try methods leave much to he desired on the score of accuracy and economy.

It is a principal object of my invention to provide a machine which shall obviate the difliculty described by cutting all of the sharply curved portions of the surface of a last at one operation, thereby eliminating; the unavoidable inaccuracies consequent upon an attempt to form and fit together two portions oi an irregularly and sharply curved. surface by two independent ope "L tions.

The question of standardization oi? last dimensions has become oi growing importance during the last few years, owing to the rapidly increasing use of machinery for operations previously performed by hand. Standardization of last dimensions will simplify the adjustment of the machinery to a great degree. In particular, the position of the thimble hole is oi extreme importance, since the shoe is mounted in many machines upon a spindle which en- "gages this hole. It is another important ohject oi? my invention to provide means for grading these thimble holes in standard position and, in addition, to so grade them while the lasts are being out.

My invention in its broadest aspect contemplates mounting the block in the lathe by engagement with portions remote from its principal axis, and turning the entire upper (including the terminal) operative surface of the last at one continuous operation. The difliculty and expense inherent in the present practice of independently shaping and finishing; the ends of the last are thereby avoided.

In another aspect my invention contemplates forming in the last hlpclr, a hole arranged to serve as the thimble hole in the completed last, mounting the model and the block in the lathe with their thimble holes similarly placed", and bringing the model wheel and the cutter simultaneously to the respective holes during-their traverses. This insures a uniform position of the thimble hole in waded lasts of all sizes and widths, and facilitates: machine shoemalrinm The machine shown, by which this process may be practised, comprises lathe centers. engaging. the model and block in their thimbl'e holes, whereby the location of the thimble hole in the last out is rendered positive and accurate.

A feature of my invention comprises a chucking instrumentality for a last lathe arranged to engage a last only upon its substantially flat portions. The access of the model wheel and cutter to the sharply curved parts of the operative surfaces of the model and last is therefore uninterfered with, and all such parts of the last may be cut at one continuous operation.

Another feature of my invention comprises lathe centers engaging the model or block or both of them at substantial distances from their principal axes. of the model and block are thereby left free for the operations of the model wheel and cutter, and the ends and sides of the last may then be cut at one continuous opera tion.

A further feature of the invention is a last block having a hole which is to serve as the thimble hole in the completed last.

A further feature of the invention is a last block having a hole therein arranged to cooperate with a chucking instrumentality and to serve as a thimble hole of the completed last.

Other features of the invention, comprising certain arrangements and combinations of parts, will be described in the following specification and pointed out in the claims.

In the drawings which illustrate the best way of practising the invention now known to me:

Figure 1 is a diagrammatic plan view of the essential working parts of a last lathe in which my invention has been embodied;

Fig. 2 shows a last as it comes from the lathe when turned under the practice here' tofore used;

Fig. 3 shows a last as it comes from the lathe, when turned in accordance with my invention;

Figs. 4 and 5 are details of the heel and toe of the last shown in Fig. 3;

Fig. 6 is a sectional detail showing the heel center, and

Fig. 7 is a detail showing the model wheel passing over the heel of the model.

The model wheel 10 and its carriage 11, the cutter 12 -and its. carriage 13 and the length grader 14 and connecting mechanism adjustable at 15 are all of ordinary construction. The model and block are mounted and driven in a swing frame by the ordinary mechanism. These'parts of the lathe have been familiar to workers in the last making art for decades and no further description of them is thought necessary.

The dogs or centers, themselves upon which the model and block are hung are of The ends peculiar construction. The model heel center is a U-shaped clamp 16 engaging the top and bottom of the heel portion of the model. An expansionsleeve device extends into the thimble hole 18 of the model, the screw 19 being threaded in a bushing 20, as shown in Fig. 6, which fits the thimble hole, and wedging into a split sleeve 21 so that the tightening of the screw 19 forces the members of the sleeve 21 down firmly on the bottom of the thimble hole as well as spreads them to grip the sides of the hole. The last is thus firmly clamped against the lower arm 22 of the U which is pivotally latched at 23 to the main body of the clamp, so that it can turn to facilitate the mounting of the. model. My invention is not limited to the. form of clamp shown, but may be practised by the aid of any convenient clamping device.

The model toe center 23 has a drop neck construction, as shown, and enters a hole bored in the tread face of the model at the toe. The widths of the open portion 24- of the U, and of the crooked portion 25 of the toe center are sufficient to permit the entrance of the model wheel 10, so that it can engage the entire surface at the ends of the model. A pivotal stop member 26 is mounted on the heel center. having a limited motion above and below the plane of the paper in Fig. 1. This stop member slxips at such a position as to allow the operative surface of the model wheel to contact the tip end of the heel, but holds the model wheel from dropping farther into and locking on the U arms, see Fig. 7. It will be seen then that the operative surface of the model wheel contacts the entire surface of the last except at the top and bottom of the heel and at the bottom of the toe tip, where the model. is engaged by the centering instrumentalities.

The block heel center 27 is similar to the model heel center, but is slightly smaller, so that the cutter blade will not engage it. The toe center 28 is dropped like the center 23, but is shorter, and engages the block be.- low the axis of rotation, as shown. Its lateral dimensions are slightly smaller than the corresponding dimensions of the model toe center, in order to protect the cutter blade.

The block is prepared by sawing out the two faces at 29 and 30, and boring the (himble hole 81. It is then clamped on the center 27 just as the model is on the center 10, and the center 28 is engaged with it.

The turning operation as ordinarily con-- ducted will then produce a last completely formed except for finger-like ieces 34- on the top and bottom of the. beef and on the. bottom of the toe tip. The surface of the last is almost flat in all these three places, and the cutting down of these fingers to continuations of these almost flat surfaces may be very simply and accurately done out oi the lathe. as the surrounding portions of the surfaces furnish guides which are easy to :lollow. The actual width of these finger pieces will depend upon the diameter of the model wheel used. The old-fashioned inch wheel will ride almost on. the outer edge ol the last and the outer edge of the el. up 1G. The modern If, inch to inch wheel will descend deeper into the angle between the clamp and the flat last surface at this point, and make the fingers much narrower.

ln the ordinary lathe the toe centers 23 and 528 are dead, but my invention contemlates driving them it necessary, since some shapes of lasts will prove harder to hold than others. The toe centers may be geared to the heel centers in the same way that these centers are now geared to each other. A positive and rigid support for the model and block will result, and all possible disadvantages of an offset center avoided.

My invention also provides for the grading ot the thimble holes in the lasts being cut; The frame of the lathe is provided with two scales 29 and 30, in connection with two pointers 31 and 32 on the model wheel carriage and the cutter carriage respectively.

'l hese scales are adjusted by means of the slots shown, so that when the center of the model wheel is opposite the center of the screw 19, and the center of the cutter is opposite the center of the screw 33, the two scale readings are the same. After every adjustment oi? the length grader ll (which will disturb this adjustment) the connection loosei'ied, and the two carriages moved until both scales again have this reading, when the connection 15 is again tightened. ll ith the lathe in this adjustment the last will be cut with the hole 31 in the same relative location as that of the thimble hole in the model, since the model. wheel and the cutter will always reach similar points upon the last and model at the same time in their t r a erse.

l am enabled, by means of my invention, to perform in one operation what has been known the turning of the last, the shaping ol? the ends, and the location of the thimble hole according to grade, for which three separate and mechanically independent operations have heretofore been red u ired.

A very important advantage of the invention resides in its provision for supporting the block and model in the ordinary positions and rotating them about their principal or longitudinal axes, that is, axes pass ing approximately through the toe and the center ot the heel. Ordinary width grading is therefore possible, since the proper and necessary width grading axis has remained undisturbed.

swing mechanism for carrying a complete model last and block and presenting them to the wheel and cutter, respectively, and means for chucking and driving the model constructed and arranged to engage the model only upon substantially [lat portions at one end and to drive it through such engagement about an axis passing substantially through the center of the heel, said means being organized to insure free access of the model wheel to the driven end of the model.

2. In a last lathe, a model wheel, a cutter, swing mechanism for carrying a complete model last and block and presenting them to the wheel and cutter, respectively, and means for chucking the model constructed and arranged to engage the heel of the model only upon portions remote from its axis of rotation and to clear its ends by more than the thickness of the model wheel to elfect free access of the model wheel to an end and the curved lateral surface of the model heel, and the finishing oi the corresponding parts of the block by the cutter at one operation.

3. In a last lathe, a model wheel, a cutter, swing mechanism for carrying a model and block and presenting them to the wheel and cutter, respectively, and means for chucking the model constructed and arranged to rotate the model about a central longitudinal axis and to engage the model only upon the sole and the top of the cone to provide free terminal access of the model wheel to the model, and the engagement of the cutter with an end and all of the lateral uppercontacting surface of the last at one opera tion.

In a last lathe, a model wheel, a cutter, swing mechanism for carrying a model and. block and presenting them to the wheel and cutter respectively, width grading mechanism coin nising a model wheel, and means for chucking the model and block constructed and arranged to engage the operative surfaces of the model and block upon their lower faces to permit the model wheel and cutter to engage respectively all points of the operative surllaces of the model and last being out except parts of the tread faces and to produce thereby a last width-graded in the ordinary manner and completely turned at the heel and toe ends.

5. In a last lathe. a i'nodel wheel, a cutter,

swing mechanism for holding a model and block and presenting them to the wheel and block respectively, comprising members arranged to engage on opposite sides the heels of both the model andv the block and to provide uninterrupted access for the operative surfaces of the model wheel and of the cut-- ter to the entire lateral peripheries of the heels of the model and the last being cut respectively.

6. In a last lathe, a model wheel, a cutter,

and swing mechanism for holding an entire last model and a block and presenting them to the wheel and cutter respectively, comprising means for engaging in the direction of gage a definite gage point on the model and means for similarly engaging a similar gage point on the block, said gage points block in such manner that the hole in the block is graded into the same position relatively to the surface of the finished last as that of the thimble hole relatively to the surface of the model.

'8.- In a last lathe, a model wheel, a cutter, grading mechanism, swing mechanism for holding a model-and block and presenting them to the wheel and cutter respectively, and means for mounting the model and block in said swing mechanism arranged to engage the model in its thimble hole and the block in a corresponding hole, said instrumentalities having an adjustment cooperating with the grading mechanism to cause the model wheel and cutter to reach the centers of the two said holes simultaneously.

9. In a last lathe, a model wheel, a cutter, and swing mechanism constructed and arranged to engage only at points remote from their longitudinal axes, a model and a block having thimble holes, and to provide access of the model wheel and cutter to all substantially curved parts of the operative surface of the model and of the last being out, there being provision for adjustment between said instrumentalities, for causing said wheel and cutter to reach said holes simultaneously.

7 10. In a last lathe, a model wheel, a cut ter, and swing mechanism for holding a model and block and presenting them to the wheel and cutter respectively, comprising means rotating the model about its principal longitudinal axis arranged to embrace and hold the heel of the model and spaced from the lateral periphery thereof by more than the thickness of the model wheel to provide clearance for the operative surface of the model wheel to contact with the entire lateral periphery of the heel and to support the wheel as it passes over the tip of the heel.

ll. In a last lathe, a model wheel, a cutter, swing mechanism for holding a model and a block and presenting them to the wheel and cutter respectively and rotating them about their principal longitudinal axes, arranged to clear the lateral periphcry of the last by more than the thickness of the model wheel to permit all sharply curved portions of the last to fall into contact with the model wheel, and an abutment to the rear of the model for supporting the model wheel as it rolls over the end of the heel.

12. In a last lathe, a model wheel, a cutter, swing mechanism for holding a model and block and presenting them to said wheel and cutter respectively, arranged to clear the lateral periphery of the last by more than the thickness of the model wheel to provide access of the model wheel to all sharply curved portions of the last, and an abutment constructed and arranged to swing either side of the axis of rotation of the last, to support the model wheel as it rolls over the end of the heel.

13. In a last lathe, a model wheel, a cutter, and swing mechanism for holding a model and block, driving them about their principal longitudinal axes, and presenting them to the wheel and cutter respectively, comprising a member engaging the sole of the model behind the toe tip and a member engaging the heel of the model constructed and arranged to clear the lateral periphery of the heel by more than the thickness of the model wheel to provide unobstructed access of the model wheel to the end of the heel.

14:. In a last lathe, a model wheel, a cutter, and swing mechanism for holding a model and block, driving them about their principal longitudinal axes and presenting them to the wheel and cutter respectively comprising a member engaging the forepart of the model below the line of centers and constructed to permit access of the model wheel to the entire upper surface of the toe and a member engaging the heel of the model only at portions remote from its axis of rotation and clearing the lateral periphery of the heel by more than the thickness of the model wheel in such manner as to permit the end of the model heel to drop to the model wheel.

15. In a last lathe, swing mechanism for carrying a block, a cutter, and a toe center engaging the block below the toe of the last being cut, and a C-shaped member embracingthe model heel providing clearances for lli) leas es ti?! the cutter to contact with the entire upper and terminal surface of the toe and the entire lateral surface of the heel.

16. That improvement in the art of manufacturing lasts which consists in engaging :mblocl; with the lathe at points remote from the principal longitudinal axis of the block, and then turning from the block the entire effective upper and terminal surface of the last at one continuous operation.

17. That improvement in the art at manufacturing lasts which consists in mounting the entire block in the lathe by its lateral portions, and turning from the block the complete terminal and upper operative surface of a last at one continuous operation.

18. That improvement in the art of manufacturing lasts which consists in boring in the block a hole which is to serve as the thimble hole of the completed last, mounting the block and the model with said hole and the thimble hole 01 the model similarly placed, and bringing the cutter and the model wheel to said holes respectively at the same instant in their traverses, whereby the hole is graded into the same relative position in all lasts cut.

19. A last bloclr having a hole bored therein, constructed and arranged to serve as the thimble hole of the completed last.

20. A last block having a hole bored therein arranged to cooperate with a chucking instrumentality and to serve as the thimble hole of the completed last.

21. A last block having its upper and lower rear portions shaped approximately to the contour and position oi": the tip of the cone and the bottom oi: the heel of a completed last.

22. ln a last lathe, a model wheel, and mechanism for holding and presenting a model to the wheel comprising mechanism engaging the top of the cone and the bot tom of the heel and arranged to provide for t contact of the model wheel with the entire end of the model heel.

23. ln a last lathe, a model wheel and mechanism for holding and presenting a model to the wheel comprising a member engaging the top of the cone and the bottom of the heel and arranged to provide for corn tact of the model wheel with the entire end oil? the model heel, and a member arranged to support the model wheel as it rolls over the end oi? the heel and to prevent its effective surface falling past the heel tip.

2%. ln a last lathe, a model wheel and mechanism for holding and presenting a model to the wheel comprising a C-shaped member engaging the top of the cone and the bottom of the heel, and an abutment arranged to swing either side of the axis of rotation of the last for supporting the model wheel in contact with the tip of the heel.

ln a last lathe, a model wheel, a cutter, mechanism for holding a last model having a thimble hole and a last block having a corresponding hole and for causing engagement between them and the wheel and cutter, respectively, and means constructed and arranged to cause the model wheel and cutter to reach simultaneously the centers of the two holes, respectively.

2'6. In a last lathe, a model wheel, a cutter, mechanism for holding a last model having a thimble hole and a last block having a corresponding hole, said mechanism causing engagement between the model and the wheel and the block and cutter respectively and comprising members engaging in said holes respectively, and means constructed and arranged to cause the model wheel and cutter to reach simultaneously the centers of the two holes, respectively.

27. in a last lathe, a model wheel and mechanism for holding and presenting a model to the wheel comprising a member en gaging the top of the cone and the bottom Or the heel portion of the model and arranged to provide for contact of the model wheel with the entire end of the model heel, and a second member carried by the first mentioned member to support the model wheel as it rolls over the end of the model heel.

In testimony whereof I have signed my name to this specification.

PAUL F. W. C. KRIPPENDORF.

It is hereby certified that in Letters Patent No. 1,335,062, granted March 30, 1920, upon the application of Paul F. W. C. Krippendorf, of Lynn, Massachusetts, for an improvement in The Manufacture of Lasts, errors appear requiring correction as follows: In the printed specification, page 4, line 19, claim 7, after the word cutter insert a comma, and in the drawings, Sheet 2, Fig. 4 should appear as shown below instead of as shown in the patent:

and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 18th day of May, A. D., 1920.

SEAL] M. H. COULSON,

Acting Commissioner of Patents.

Correctlons n Letters Patent No.1,335,062. 

